A mere four kilometers from the famous Nazca Lines is an avenue of stone spirals, snaking several meters down into the desert sand. Well-preserved remnants of the advanced Nazca Culture, you can find these spirals throughout the southern coast of Peru and northern Chile. They are the entrances to a complex irrigation system that transformed the arid desert landscape into fertile, habitable land.
The Nazca
The Nazca inhabited Peru’s southern coast from 200 BC to 650 AD. Known for their distinctive textile patterns, their use of skull manipulation, unique funerary practices, and the mysterious Nazca Lines, the Nazca were also incredible engineers. Perhaps their finest engineering achievement was the system of aqueducts that stored water and irrigated their fields. The Nazca first implemented this system sometime between 300 and 500 AD.
Spiral “ojo” of the Cantalloc Aqueduct up close. Photo: Daniel Prudek/Shutterstock
The Nazca called this system of aqueducts “puquios.” At first, archaeologists believed the spirals to be wells, but they are instead an entrance to a long channel of underground water. They spread out for substantial distances, pushing water to the driest parts of the region and limiting evaporation. The water originates from springs in the mountains.
There are two main variations of puquios. One type is an open-air, narrow ditch, lined with smooth stones. The other is an underground gallery which goes 10 to 15m below the surface to an aquifer. The water in this aquifer then travels down in a winding fashion, this keeps the flow steady and avoids flooding the fields during months of higher precipitation.
The characteristic spiral entrance is not just for aesthetics. The funnel-shaped eye, or “ojo,” houses a ventilation shaft and the stones act as a staircase to enter the aqueduct.
The shaft allows the collection of water when it rains but also harnesses the wind to push water through the system. You can find several ojos close together, roughly 10m apart, as seen in the photo below.
Cantalloc aqueduct in Nazca. Photo: Daniel Prudek/Shutterstock
Still in use today
Incredibly, the system is still in use, showing that the Nazca were far ahead of their time. The Nazca Valley area has 29 puquios and the rest are spread through the Taruga and Las Trancas Valleys, and northern Chile.
There are 43 puquios still in operation, with slight modern modifications but retaining their original design.
This ancient hydraulic system usually gets compared to qanats, the sophisticated aqueducts found in Iran. While the concept and subterranean design are relatively similar, a qanat normally surfaces in a garden or oasis.
